ACT Reading Key Ideas and Details: central idea, summary, inference, cause and relationships - complete overview

Key Ideas and Details is the largest of the three ACT Reading reporting categories, about 52 to 60 percent of the section. It groups the skills of reading for the main point and its support. This site breaks the category into five dot points, from the central idea to relationships between ideas. This overview maps the five skills, how they connect, and how to study them.

The five Key Ideas and Details skills

Each skill is a way of reading the substance of a passage.

• Central idea and theme. Stating the main point of an informational passage or the theme of a literary one as a full idea. See central idea and theme.
• Summarizing a passage. Keeping the main point and key support, faithfully and in balance. See summarizing a passage.
• Drawing inferences. Taking the smallest supported step beyond what the passage states. See drawing inferences.
• Sequence and cause and effect. Following order through flashbacks and telling cause from correlation. See sequence and cause and effect.
• Relationships between ideas. Naming comparison, contrast, support, and qualification, and reading paragraph function. See relationships between ideas.

The thread through every skill: the whole passage, proven by lines

Two ideas tie the category together. The first is the whole passage: the central idea, a summary, and the relationships all have to fit everything the passage does, not one part, which is why the trap answers are so often a topic, a detail, or a one-sided reading. The second is evidence: every reading, even an inference, rests on a specific line or a clear chain of reasoning in the text, never on outside knowledge or a plausible story. Read for the whole-passage point, prove each step from the text, and this category, the biggest in the section, becomes the most reliable.

How the skills are tested

• Main-idea and summary questions: the best statement of the central idea, theme, or summary of a passage or paragraph.
• Inference questions: what the passage suggests, implies, or most likely indicates, not stated outright.
• Detail, sequence, and cause questions: what happened, in what order, and what the passage says caused what.

How to study Key Ideas and Details

1. Nail the whole-passage point first. For every passage, state its central idea or theme in a sentence before answering.
2. Distinguish topic, idea, and detail. Practice rejecting the topic-only and detail-only trap answers.
3. Keep inferences small. Take the step the evidence forces; refuse the over-reach.
4. Separate cause from correlation. Demand a stated causal link, and watch for hidden third causes.
5. Track the transitions. Use however, despite, and for example to read relationships and paragraph function.

For the official exam materials

ACT publishes the Reading standards and reporting categories and free official practice. See the ACT Reading standards page and the ACT exam sections and structure page. Always study from the current official materials, because the reporting categories and the question style are set by ACT.